<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Form 表单简单上传</title>
    <style>h1, h2 {font-weight: normal;}#msg {margin-top:10px;}</style>
</head>
<body>

<h1>Form 表单简单上传（兼容 IE8）</h1>
<div>最低兼容到 IE6 上传，不支持 onprogress</div>

<form id="form" target="submitTarget" action="" method="post" enctype="multipart/form-data" accept="*/*">
    <input id="name" name="name" type="hidden" value="">
    <input name="success_action_status" type="hidden" value="200">
    <input id="success_action_redirect" name="success_action_redirect" type="hidden" value="">
    <input id="key" name="key" type="hidden" value="">
    <input id="Signature" name="Signature" type="hidden" value="">
    <input name="Content-Type" type="hidden" value="">
    <input id="x-cos-security-token" name="x-cos-security-token" type="hidden" value="">

    <!-- file 字段放在表单最后，避免文件内容过长影响签名判断和鉴权 -->
    <input id="fileSelector" name="file" type="file">
    <input id="submitBtn" type="button" value="提交">
</form>
<iframe id="submitTarget" name="submitTarget" style="display:none;" frameborder="0"></iframe>

<div id="msg"></div>

<script src="common/cos-auth.min.js"></script>
<script>
    (function () {

        // 请求用到的参数
        var Bucket = 'test-1250000000';
        var Region = 'ap-guangzhou';
        var protocol = location.protocol === 'https:' ? 'https:' : 'http:';
        var prefix = protocol + '//' + Bucket + '.cos.' + Region + '.myqcloud.com/';
        var form = document.getElementById('form');
        form.action = prefix;

        // 对更多字符编码的 url encode 格式
        var camSafeUrlEncode = function (str) {
            return encodeURIComponent(str)
                .replace(/!/g, '%21')
                .replace(/'/g, '%27')
                .replace(/\(/g, '%28')
                .replace(/\)/g, '%29')
                .replace(/\*/g, '%2A');
        };

        // 计算签名
        var getAuthorization = function (options, callback) {
            // var url = 'http://127.0.0.1:3000/sts';
            var url = '../server/sts.php';
            var xhr = new XMLHttpRequest();
            xhr.open('GET', url, true);
            xhr.onreadystatechange = function (e) {
                if (xhr.readyState === 4) {
                    if (xhr.status === 200) {
                        var credentials;
                        try {
                            credentials = (new Function('return ' + xhr.responseText))().credentials;
                        } catch (e) {}
                        if (credentials) {
                            callback(null, {
                                XCosSecurityToken: credentials.sessionToken,
                                Authorization: CosAuth({
                                    SecretId: credentials.tmpSecretId,
                                    SecretKey: credentials.tmpSecretKey,
                                    Method: options.Method,
                                    Pathname: options.Pathname,
                                })
                            });
                        } else {
                            console.error(xhr.responseText);
                            callback('获取签名出错');
                        }
                    } else {
                        callback('获取签名出错');
                    }
                }
            };
            xhr.send();
        };

        // 监听上传完成
        var Key;
        var submitTarget = document.getElementById('submitTarget');
        var showMessage = function (err, data) {
            console.log(err || data);
            document.getElementById('msg').innerText = err ? err : ('上传成功，ETag=' + data.ETag);
        };
        submitTarget.onload = function () {
            var search;
            try {
                search = submitTarget.contentWindow.location.search.substr(1);
            } catch (e) {
                showMessage('文件 ' + Key + ' 上传失败');
            }
            if (search) {
                var items = search.split('&');
                var i, arr, data = {};
                for (i = 0; i < items.length; i++) {
                    arr = items[i].split('=');
                    data[arr[0]] = decodeURIComponent(arr[1] || '');
                }
                showMessage(null, {url: prefix + camSafeUrlEncode(Key).replace(/%2F/g, '/'), ETag: data.etag});
            } else {
            }
        };

        // 发起上传
        document.getElementById('submitBtn').onclick = function (e) {
            var filePath = document.getElementById('fileSelector').value;
            if (!filePath) {
                document.getElementById('msg').innerText = '未选择上传文件';
                return;
            }
            Key = 'dir/' + filePath.match(/[\\\/]?([^\\\/]+)$/)[1]; // 这里指定上传目录和文件名
            getAuthorization({Method: 'POST', Pathname: '/'}, function (err, AuthData) {
                // 在当前目录下放一个空的 empty.html 以便让接口上传完成跳转回来
                document.getElementById('success_action_redirect').value = location.href.substr(0, location.href.lastIndexOf('/') + 1) + 'empty.html';
                document.getElementById('key').value = Key;
                document.getElementById('signature').value = AuthData.Authorization;
                document.getElementById('x-cos-security-token').value = AuthData.XCosSecurityToken || '';
                form.submit();
            });
        };
    })();
</script>

</body>
</html>
